首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   19822篇
  免费   1144篇
  国内免费   429篇
耳鼻咽喉   59篇
儿科学   299篇
妇产科学   379篇
基础医学   1581篇
口腔科学   345篇
临床医学   2510篇
内科学   3193篇
皮肤病学   145篇
神经病学   379篇
特种医学   757篇
外科学   6450篇
综合类   2471篇
预防医学   777篇
眼科学   70篇
药学   1193篇
  18篇
中国医学   402篇
肿瘤学   367篇
  2024年   20篇
  2023年   421篇
  2022年   720篇
  2021年   1134篇
  2020年   1192篇
  2019年   1055篇
  2018年   998篇
  2017年   694篇
  2016年   735篇
  2015年   690篇
  2014年   1536篇
  2013年   1535篇
  2012年   1039篇
  2011年   1164篇
  2010年   957篇
  2009年   937篇
  2008年   859篇
  2007年   775篇
  2006年   707篇
  2005年   611篇
  2004年   577篇
  2003年   470篇
  2002年   404篇
  2001年   318篇
  2000年   277篇
  1999年   199篇
  1998年   189篇
  1997年   147篇
  1996年   120篇
  1995年   121篇
  1994年   102篇
  1993年   94篇
  1992年   94篇
  1991年   38篇
  1990年   48篇
  1989年   49篇
  1988年   61篇
  1987年   57篇
  1986年   34篇
  1985年   37篇
  1984年   32篇
  1983年   21篇
  1982年   24篇
  1981年   18篇
  1980年   18篇
  1979年   26篇
  1978年   9篇
  1977年   8篇
  1976年   8篇
  1975年   8篇
排序方式: 共有10000条查询结果,搜索用时 890 毫秒
1.
Menopause is generally experienced as a biopsychosocial process involving physiological changes, and influenced by a wide range of psychological, social and cultural factors. The loss of ovarian oestrogen production may cause debilitating symptoms, including hot flushes, night sweats, sleep disturbance, vaginal dryness, dyspareunia, bladder dysfunction, loss of libido, and mood changes. Experience of the menopause transition varies widely between individuals, depending on the age of onset, personal health and wellbeing, social context, environment and culture.Hormone Replacement Therapy (HRT) remains the most effective treatment for the management of vasomotor symptoms and vaginal dryness, but has no proven role in the treatment of chronic diseases of ageing. Treatment should be individualized, and for most healthy women aged 50–59 years the risks of HRT are low. An understanding of the pathophysiology of menopausal symptoms and the risks and benefits of both hormonal and non-hormonal treatments assists in the individual management of patients.  相似文献   
2.
3.

Objectives

Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database.

Methods

Records from 39,812 patients undergoing coronary artery bypass grafting or valve operations (2008-2016) and extubated within 24 hours were stratified according to extubation time between 06:00 and 18:00 (day) or between 18:00 and 6:00 (overnight). Outcomes including reintubation, mortality, and composite morbidity-mortality were evaluated using hierarchical regression models adjusted for Society of Thoracic Surgeons predictive risk scores. To further analyze extubation during the night, a subanalysis stratified patients into 3 groups: 06:00 to 18:00, 18:00 to 24:00, and 24:00 to 06:00.

Results

A total of 20,758 patients were extubated overnight (52.1%) and were slightly older (median age 66 vs 65 years, P < .001) with a longer duration of ventilation (4 vs 7 hours, P < .001). Day and overnight extubation were associated with equivalent operative mortality (1.7% vs 1.7%, P = .880), reintubation (3.7% vs 3.4%, P = .141), and composite morbidity-mortality (8.2% vs 8.0%, P = .314). After risk adjustment, overnight extubation was not associated with any difference in reintubation, mortality, or composite morbidity-mortality. On subanalysis, those extubated between 24:00 and 06:00 exhibited increased composite morbidity-mortality (odds ratio, 1.18; P = .001) but no difference in reintubation or mortality.

Conclusions

Extubation overnight was not associated with increased mortality or reintubation. These results suggest that in the appropriate clinical setting, it is safe to routinely extubate cardiac surgery patients overnight.  相似文献   
4.
5.
6.
7.
8.
Arthroscopic acromioclavicular joint excision is a commonly performed but technically demanding procedure. Incomplete excision can leave residual symptoms. We present a simple, reproducible technique ensuring satisfactory excision of the joint.  相似文献   
9.
Polyethylene (PE) has been used extensively in knee arthroplasty since the mid 20th century. Progress in material manufacturing and processing has led to newer polyethylenes over last few decades with different material properties. It has been established that PE wear in knee arthroplasty causes particle induced osteolysis which is the main reason for late failure and requires revision surgery. Although there are various causes of wear, the properties of PE have long been a matter of investigation as a contributory factor. The advent of newer highly cross linked PE has been shown to improve wear rates in hip arthroplasty but the benefits have not been shown to be of the same degree in knee arthroplasty. The laboratory and clinical studies so far are limited and slightly conflicting in their conclusions. The risks of using highly cross linked PE in knee arthroplasty include tibial post fracture, disruption of locking mechanism, liner fracture which can lead to increased wear and osteolysis. The current evidence suggests that highly cross linked polyethylenes should be used with caution and only considered in younger active patients. The results of a recently completed randomized trial to compare the conventional with high molecular weight PE in knee arthroplasty are awaited.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号